Small amount of algae - SWG pool

[jandersen13]

Hi everyone,

The pool has been running fantastic all summer with clear sparkling water and testing levels staying in check. Came out to the pool today and noticed some algae build up in the corners and side angled walls. I brushed it all up, backwashes and added 1/2 gallon of liquid bleach.

I ran my test numbers and have this:
FC - 7.5
CC - 0.5
TA - 100
PH - 8.0 (this is what it normally runs at steady with SWG - I did put Muriatic acid in 5 days ago to lower to 7.6)
CYA - 60
Salt - 3200

Any thoughts on how to get those CC’s back to zero? I believe that is my issue. But I’m also not sure how it happened. The weather has been cooler at night and we’ve been heating during the day. Probably a bit less swim activity than normal for the past week. Any thoughts?

 

[YippeeSkippy]

Have you considered performing an Overnight Chlorine Loss Test?
Overnight Chlorine Loss Test

Lets rule out a need to SLAM if we can nip it in the bud.

Also perhaps this area needs a bit more brushing and circulation to expose it to chlorine.

Maddie

 

[YippeeSkippy]

Of course you can just head on and start a SLAM process right off too.... probably needed actually.

 

[duraleigh]

Any thoughts on how to get those CC’s back to zero? I believe that is my issue.

No, it's not. A CC test result of .5 ppm is treated EXACTLY as if it were zero.

That said, with those pretty good numbers, I would take the FC to double the current value and brush everything thoroughly. It will likely eradicate the small amount of algae you have. Perform an OCLT the following evening to see if you got all the algae.

 

[jandersen13]

Thanks everyone. I bumped up the chlorine but looks like i need to a bit more, to double. Just added enough to do that. I'm running the vacuum tonight and then will check chlorine tonight and first thing tomorrow.

Any ideas of why I got the algae in the first place though as things were running smoothly? Does this happen to you guys too? My numbers have been within range.

 

[duraleigh]

As humans, we all sorta want black and white answers. 4.00 FC = no algae.......3.99 FC = algae. We also all know that it just doesn't work like that. Too many variables to pool maintenance so we learn that our ranges aren't always perfect....letting some algae slip in.

TFP teaches to understand the underlying nature of pool water chemistry so when things don't always work as perfectly as we would like, we know exactly what to do about it.

 

[jandersen13]

Good advice! I was hoping for a simple answer, but you're right! Thanks.